Continuity mistake: In the scene where D-Fens was going to get on the bus, there is a young black woman seen standing at the end of the bench clad in a lavender tank top, and is later seen getting on board. D-fens changes his mind and turns around and walks. She is later seen in MacArthur Park dancing with a small band. (00:32:50 - 00:36:40)
Plot hole: Foster served in the military and even received a Purple Heart as indicated by the plaque in his mother's home. Yet he needs a kid to explain to him how to handle an M72 rocket launcher. A weapon introduced in the 60s and thus well within his time at the military.
Continuity mistake: During the showdown on the pier, a Richard Marx poster over the skull graffiti disappears. (01:38:00 - 01:39:44)
Visible crew/equipment: In the beginning of the movie, during the traffic jam, the camera pans from D-FENS to the car in front of him and then to the right to the car with the Garfield toy stuck to the window. You can see equipment (a statue, some wires and a white screen) in the reflection of the window. (00:01:30)